Removes grab input window and extra grab and ungrab in X11WholeScreenMoveLoop

chrome/browser/ui/views/tabs/tab_drag_controller.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/views/tabs/tab_drag_controller.h"
 
 #include <math.h>
 #include <set>
 
 #include "base/auto_reset.h"
@@ skipping 1159 matching lines @@
         dragged_widget->GetNativeView());
 #endif
   dragged_widget->SetVisibilityChangedAnimationsEnabled(false);
   Attach(dragged_browser_view->tabstrip(), gfx::Point());
   AdjustBrowserAndTabBoundsForDrag(last_tabstrip_width,
                                    point_in_screen,
                                    &drag_bounds);
   WindowPositionManagedUpdater updater;
   dragged_widget->AddObserver(&updater);
   browser->window()->Show();
+  // Set capture after the newly created browser widget is visible.
+  attached_tabstrip_->GetWidget()->SetCapture(attached_tabstrip_);

[varkha, 2014/05/21 20:07:20]

This makes sure that capture is really where we think it is after calling
Attach(). Attach() would normally set capture on attached widget but with Aura
fails to do so because of IsVisible() check in Window::SetCapture(). This was
wrong before but worked because of additional capture in X11WholeScreenMoveLoop.
Simplifying X11WholeScreenMoveLoop exposed this.

   dragged_widget->RemoveObserver(&updater);
   dragged_widget->SetVisibilityChangedAnimationsEnabled(true);
   // Activate may trigger a focus loss, destroying us.
   {
     base::WeakPtr<TabDragController> ref(weak_factory_.GetWeakPtr());
     browser->window()->Activate();
     if (!ref)
       return;
   }
   RunMoveLoop(drag_offset);
@@ skipping 747 matching lines @@
        it != browser_list->end(); ++it) {
     if ((*it)->tab_strip_model()->empty())
       exclude.insert((*it)->window()->GetNativeWindow());
   }
 #endif
   return GetLocalProcessWindowAtPoint(host_desktop_type_,
                                       screen_point,
                                       exclude);
 
 }